Frees up LR on arm for use by the register allocator.

runtime/vm/intermediate_language_arm.cc

 // Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/globals.h"  // Needed here to get TARGET_ARCH_ARM.
 #if defined(TARGET_ARCH_ARM)
 
 #include "vm/intermediate_language.h"
 
 #include "vm/cpu.h"
@@ skipping 182 matching lines @@
     if (false_value != 0) {
       __ AddImmediate(result, Smi::RawValue(false_value));
     }
   }
 }
 
 
 LocationSummary* ClosureCallInstr::MakeLocationSummary(Isolate* isolate,
                                                        bool opt) const {
   const intptr_t kNumInputs = 1;
-  const intptr_t kNumTemps = 0;
+  const intptr_t kNumTemps = 1;
   LocationSummary* summary = new(isolate) LocationSummary(
       isolate, kNumInputs, kNumTemps, LocationSummary::kCall);
   summary->set_in(0, Location::RegisterLocation(R0));  // Function.
+  // LR is clobbered by blx.
+  summary->set_temp(0, Location::RegisterLocation(LR));

[Florian Schneider, 2014/09/25 09:49:22]

Calls clobber all registers, so I'm not sure if this is necessary.

[zra, 2014/09/25 18:11:27]

Done.

   summary->set_out(0, Location::RegisterLocation(R0));
   return summary;
 }
 
 
 void ClosureCallInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
   // Load arguments descriptor in R4.
   int argument_count = ArgumentCount();
   const Array& arguments_descriptor =
       Array::ZoneHandle(ArgumentsDescriptor::New(argument_count,
@@ skipping 4869 matching lines @@
     __ vsqrtd(result, val);
   } else if (kind() == MathUnaryInstr::kDoubleSquare) {
     const DRegister val = EvenDRegisterOf(locs()->in(0).fpu_reg());
     const DRegister result = EvenDRegisterOf(locs()->out(0).fpu_reg());
     __ vmuld(result, val, val);
   } else {
     ASSERT((kind() == MathUnaryInstr::kSin) ||
            (kind() == MathUnaryInstr::kCos));
     if (TargetCPUFeatures::hardfp_supported()) {
       __ CallRuntime(TargetFunction(), InputCount());
-      } else {
+    } else {
       // If we aren't doing "hardfp", then we have to move the double arguments
       // to the integer registers, and take the results from the integer
       // registers.
       __ vmovrrd(R0, R1, D0);
       __ vmovrrd(R2, R3, D1);
       __ CallRuntime(TargetFunction(), InputCount());
       __ vmovdrr(D0, R0, R1);
       __ vmovdrr(D1, R2, R3);
     }
   }
@@ skipping 1924 matching lines @@
   compiler->GenerateCall(token_pos(), &label, stub_kind_, locs());
 #if defined(DEBUG)
   __ LoadImmediate(R4, kInvalidObjectPointer);
   __ LoadImmediate(R5, kInvalidObjectPointer);
 #endif
 }
 
 }  // namespace dart
 
 #endif  // defined TARGET_ARCH_ARM